Known are in the art hand dryers comprising:                A housing;        A volume for receiving the hands;        A circuit for pumping air;        A drive motor which drives a fan arranged in the air circuit provided with a rotor and a stator;        A hands presence sensor in the volume and;        Operation control means;        
It is known to apply in many hand dryers with these components, heating resistors for heating the air. These are resistors that are placed at the exit of the air flow of the motor and that raise the temperature of the air in order to decrease the drying time and increase the comfort when drying in case the atmosphere of the room where the dryer is located is very cold.
The cold atmosphere, coupled with the increased evaporation of water in the hands due to the high air flow causes a considerable feeling of cold in the hands.
There are many applications including these heating elements. See for example the U.S. Pat. No. 266,229 for a “Hand Dryer apparatus” or the U.S. Pat. No. 254,101 for a “Multi-function dryer”.
The patent US20100296799 A1 “Air flow directing structure for hand dryer”, proposes an assembly consisting of a motor and a resistor, this latter placed within the circular flow of air out of the motor, which passes through the resistor and hence is directed to the element to be dried. This patent claims its compactness and low cost. However, it entails significant drawbacks:                At the cycle initiation, the air exits cold since the resistors are not yet hot;        There is a high energy consumption since the resistor consumption has to be added to that of the motor, which is very important in the case of domestic or public facilities (airport toilets, convention halls . . . ) where a large number of hand dryers is present that can be operated simultaneously;        Risk of fire due to the high temperature rise of the heating resistors or due to a motor malfunction, which may cause the lack of airflow for cooling them;        Combined with the previous point, another serious problem is that a high air flow causes dust deposits on the heating resistors since they capture the dust thus preventing the correct dissipation of heat and thus raising its temperature, the resistor becoming wrapped with “dust”, which is an excellent fuel.        The price: the resistor is one more piece, to which the necessary assurances as thermostats, thermal fuses, insulation surrounding them, materials with self-extinguishing characteristics etc must be added.        
Also known are hand dryers of the type comprising a cavity for receiving the hands, the cavity being opened upwardly and laterally, such that a top opening, a first lateral opening and a second lateral opening are defined, the cavity for receiving the hands being bounded by a first surface and a second surface provided with air injection holes for drying the hands.
A hand dryer of this type is shown in FIG. 11.
A major drawback of this type of hand dryers is that part of the water removed from the hands by the air jets that emerge from the air injection orifices are projected as droplets G by said side openings, as illustrated in FIG. 17 by the two pairs of arrows, these drops finally ending on the floor.
If these devices are used continuously, for example in public services places, projected drops cause the soil to become dirty and unpleasant. This is another issue addressed by this application.
A major drawback of this type of hand dryers is that they are very noisy.
One proposed solution is to provide a labyrinth in the air inlet of the hand dryer, that is, upstream of the motor. Examples of such solutions are described in the documents WO2012017570, JP2010279436 and JP2003180554.
Now, the inventors have found that even so, the decibel level remains high.
Also known in the art are hand dryers provided with sterilization/purification means arranged in the air circulation circuit, for example from WO2012139117, JP3028621, KR20080029143 and US2008052952.
Also are known hand dryers provided with information screens, as described for example in US2006171660 or KR200452289.